The 2009 GMC Sierra 1500 Hybrid is a two-mode hybrid vehicle that promises 40% greater fuel economy in the city and 25% better in combined driving than its conventional counterpart. The patented two-mode hybrid system is equipped with two electric motors and a powerful 6.0L gas V8 engine pushing out 332 hp and 367 lb-ft of torque. The Sierra can drive up to 30 mph on electricity, which is stored in a 300-volt battery under the rear seat of the crew cab. When the gas engine is employed, the hybrid system helps it operate in a wider band four-cylinder mode using GM's Active Fuel Management System. The half-ton full-size pickup is available in only in the Crew Cab body style with either two-wheel drive or four-wheel drive. GMC Sierra 1550 Hybrid standard features include towing up to 6,100 pounds, StabiliTrak electronic stability control system, locking rear axle and trailer package. Among the Sierra 1550 Hybrid standard safety features are dual-stage frontal air bags and head curtain side air bags.